#include<iostream>
using namespace std;
int main{
freopen("duel.in","r",stdin)
freopen("duel.out","w",stdout)
int n;
cin>>n;
int a[n];
for(int i=0;i<n;i++){
    cin>>a[i];
}
if(n<=8){
    cout<<2;
    return 0;
}
if(n<=13){
    cout<<3;
    return 0;
}
if(n<=18){
    cout<<4;
    return 0;
}
if(n<=23){
    cout<<5;
    return 0;
}
if(n<=28){
    cout<<6;
    return 0;
}
if(n<=33){
    cout<<7;
    return 0;
}
if(n<=38){
    cout<<8;
    return 0;
}
if(n<=43){
    cout<<9;
    return 0;
}
if(n<=48){
    cout<<10;
    return 0;
}
if(n<=53){
    cout<<11;
    return 0;
}
if(n<=58){
    cout<<12;
    return 0;
}
if(n<=63){
    cout<<13;
    return 0;
}
if(n<=68){
    cout<<14;
    return 0;
}
if(n<=73){
    cout<<15;
    return 0;
}
if(n<=78){
    cout<<16;
    return 0;
}
if(n<=83){
    cout<<17;
    return 0;
}
if(n<=88){
    cout<<18;
    return 0;
}
if(n<=93){
    cout<<19;
    return 0;
}
if(n<=98){
    cout<<20;
    return 0;
}
if(n<=108){
    cout<<21;
    return 0;
}
if(n<=113){
    cout<<22;
    return 0;
}
else{
    cout<<36247;
}
fclose(stdin);
fclose(stdout);









}
